diff options
Diffstat (limited to 'include/linux/elevator.h')
| -rw-r--r-- | include/linux/elevator.h | 68 |
1 files changed, 62 insertions, 6 deletions
diff --git a/include/linux/elevator.h b/include/linux/elevator.h index 1713ace808bf..b3370ef5164d 100644 --- a/include/linux/elevator.h +++ b/include/linux/elevator.h @@ -1,12 +1,16 @@ #ifndef _LINUX_ELEVATOR_H #define _LINUX_ELEVATOR_H +#include <linux/percpu.h> + +#ifdef CONFIG_BLOCK + typedef int (elevator_merge_fn) (request_queue_t *, struct request **, struct bio *); typedef void (elevator_merge_req_fn) (request_queue_t *, struct request *, struct request *); -typedef void (elevator_merged_fn) (request_queue_t *, struct request *); +typedef void (elevator_merged_fn) (request_queue_t *, struct request *, int); typedef int (elevator_dispatch_fn) (request_queue_t *, int); @@ -14,9 +18,9 @@ typedef void (elevator_add_req_fn) (request_queue_t *, struct request *); typedef int (elevator_queue_empty_fn) (request_queue_t *); typedef struct request *(elevator_request_list_fn) (request_queue_t *, struct request *); typedef void (elevator_completed_req_fn) (request_queue_t *, struct request *); -typedef int (elevator_may_queue_fn) (request_queue_t *, int, struct bio *); +typedef int (elevator_may_queue_fn) (request_queue_t *, int); -typedef int (elevator_set_req_fn) (request_queue_t *, struct request *, struct bio *, gfp_t); +typedef int (elevator_set_req_fn) (request_queue_t *, struct request *, gfp_t); typedef void (elevator_put_req_fn) (request_queue_t *, struct request *); typedef void (elevator_activate_req_fn) (request_queue_t *, struct request *); typedef void (elevator_deactivate_req_fn) (request_queue_t *, struct request *); @@ -82,19 +86,21 @@ struct elevator_queue struct kobject kobj; struct elevator_type *elevator_type; struct mutex sysfs_lock; + struct hlist_head *hash; }; /* * block elevator interface */ extern void elv_dispatch_sort(request_queue_t *, struct request *); +extern void elv_dispatch_add_tail(request_queue_t *, struct request *); extern void elv_add_request(request_queue_t *, struct request *, int, int); extern void __elv_add_request(request_queue_t *, struct request *, int, int); extern void elv_insert(request_queue_t *, struct request *, int); extern int elv_merge(request_queue_t *, struct request **, struct bio *); extern void elv_merge_requests(request_queue_t *, struct request *, struct request *); -extern void elv_merged_request(request_queue_t *, struct request *); +extern void elv_merged_request(request_queue_t *, struct request *, int); extern void elv_dequeue_request(request_queue_t *, struct request *); extern void elv_requeue_request(request_queue_t *, struct request *); extern int elv_queue_empty(request_queue_t *); @@ -103,9 +109,9 @@ extern struct request *elv_former_request(request_queue_t *, struct request *); extern struct request *elv_latter_request(request_queue_t *, struct request *); extern int elv_register_queue(request_queue_t *q); extern void elv_unregister_queue(request_queue_t *q); -extern int elv_may_queue(request_queue_t *, int, struct bio *); +extern int elv_may_queue(request_queue_t *, int); extern void elv_completed_request(request_queue_t *, struct request *); -extern int elv_set_request(request_queue_t *, struct request *, struct bio *, gfp_t); +extern int elv_set_request(request_queue_t *, struct request *, gfp_t); extern void elv_put_request(request_queue_t *, struct request *); /* @@ -125,6 +131,19 @@ extern void elevator_exit(elevator_t *); extern int elv_rq_merge_ok(struct request *, struct bio *); /* + * Helper functions. + */ +extern struct request *elv_rb_former_request(request_queue_t *, struct request *); +extern struct request *elv_rb_latter_request(request_queue_t *, struct request *); + +/* + * rb support functions. + */ +extern struct request *elv_rb_add(struct rb_root *, struct request *); +extern void elv_rb_del(struct rb_root *, struct request *); +extern struct request *elv_rb_find(struct rb_root *, sector_t); + +/* * Return values from elevator merger */ #define ELEVATOR_NO_MERGE 0 @@ -149,5 +168,42 @@ enum { }; #define rq_end_sector(rq) ((rq)->sector + (rq)->nr_sectors) +#define rb_entry_rq(node) rb_entry((node), struct request, rb_node) + +/* + * Hack to reuse the donelist list_head as the fifo time holder while + * the request is in the io scheduler. Saves an unsigned long in rq. + */ +#define rq_fifo_time(rq) ((unsigned long) (rq)->donelist.next) +#define rq_set_fifo_time(rq,exp) ((rq)->donelist.next = (void *) (exp)) +#define rq_entry_fifo(ptr) list_entry((ptr), struct request, queuelist) +#define rq_fifo_clear(rq) do { \ + list_del_init(&(rq)->queuelist); \ + INIT_LIST_HEAD(&(rq)->donelist); \ + } while (0) +/* + * io context count accounting + */ +#define elv_ioc_count_mod(name, __val) \ + do { \ + preempt_disable(); \ + __get_cpu_var(name) += (__val); \ + preempt_enable(); \ + } while (0) + +#define elv_ioc_count_inc(name) elv_ioc_count_mod(name, 1) +#define elv_ioc_count_dec(name) elv_ioc_count_mod(name, -1) + +#define elv_ioc_count_read(name) \ +({ \ + unsigned long __val = 0; \ + int __cpu; \ + smp_wmb(); \ + for_each_possible_cpu(__cpu) \ + __val += per_cpu(name, __cpu); \ + __val; \ +}) + +#endif /* CONFIG_BLOCK */ #endif |